Monovinylarene polymers and monovinylarene/conjugated diene copolymers are known and useful for a variety of purposes, It is also known to add various stabilizers to the polymers to prevent deterioration from prolonged use or processing at high temperatures, Previously stabilizers were dissolved in an organic solvent and added to the reaction solution prior to recovery of the polymer. A problem is encountered when employing certain stabilizers because of their low solubility in various typical organic solvents, Dissolving such stabilizers in solvent requires large amounts of organic solvent and high temperatures and pressures. Addition of such stabilizers is impractical in commercial processes and would require pressurized equipment. Employing solvents at elevated temperatures requires special considerations and handling techniques which contribute to the complexity and expense of commercial processes. Another disadvantage of employing such stabilizer solvent solutions, is that the stabilizers can precipitate from solution causing plugging of transfer lines and equipment.
It would therefore be desirable to develop a simple, inexpensive, and safe process for stabilizing polymers such as monovinylarene/conjugated diene copolymers.